Acer Aspire XC-1780 I5400 User Manual page 20

20 - Securing your computer
• Type the User Password and press Enter to use the computer. If
you enter the password incorrectly, a warning message appears. Try
again and press Enter.
Important
You have three chances to enter a password. If you fail to enter the
password correctly after three tries, the system halts. Press and hold
the power button for four seconds to shut down the computer. Then
turn on the computer again, and try again.